Ink billing system with changeable billing rate table

ABSTRACT

An ink billing system is used between a client company X  200  that prints information and a printer manufacturer that supplies ink cartridges (or toner) to the company X  200 . The company X  200  has a main server  210 , a plurality of in-store servers  220, 230  in communication with the main server, and a plurality of inkjet (or laser) printers  240  each having an ink cartridge  20  (or toner) for printing according to commands from the in-store server  220, 230 . When billing the company X  200  based on the number of ink shots (or drum charging time) used by the printers  240  and stored on the main server  210 , the terminal device  100  of the printer manufacturer changes the billing rate per unit of ink according to the ink shot count (or drum charging time).

RELATED APPLICATIONS

Japanese patent application No. 2005-322787 is hereby incorporated byreference in its entirety.

BACKGROUND OF THE INVENTION

1. Field of the Invention

The present invention relates to an ink billing system and ink billingmethod for invoicing based on usage of ink, toner, or other printingfluids, printing liquids, or other printing material. To simplify thefollowing discussion, the term “ink” will be used in the specificationand the claims as a generic term that represents, fluids, liquids, orother materials for printing, such materials including ink, toner,organic materials, and the like.

2. Description of the Related Art

Printers such as inkjet printers and laser printers generally printtext, pictures, or other content (referred to herein generally as“information”) on plain paper, special paper, or another recordingmedium by placing or fusing ink on the recording medium. The ink istypically stored in a cartridge which can be freely installed into andremoved from the printer. When the ink inside the cartridge is depletedin the course of using the printer, ink can be added by simply replacingthe cartridge.

Printer manufacturers also usually supply the ink and toner cartridgesthat are used in their printers to the end users, and are therefore alsoin the business of selling cartridges filled with ink.

More recently, manufacturers have developed new billing systems forcharging the printer user based on the amount of ink consumed inaddition to selling individual cartridges.

Japanese Unexamined Patent Appl. Pub. 2002-36582 discloses a billingsystem in which the inkjet printer uses optical sensors to measure howmuch ink remains in the ink cartridge, and calculates ink usage based onhow much ink remains. A data processing device connected to the inkjetprinter acquires data relating how much ink is used (referred to belowas simply “ink usage”) from the inkjet printer, and sends data relatingto ink usage over a network to a server in a service center. The billingmodule that runs on the service center server then references an inkbilling table to calculate the billing amount based on ink usage andbills the user.

Ink billing systems can be deployed in many ways. In one such system theprinter manufacturer (ink supplier) provides multiple printers to aclient company, and uses an ink billing system to invoice the client forthe ink used instead of simply selling and charging for the individualink cartridges that are used in the printers. In this scenario the inkbilling system must be able to detect how much ink was used by themultiple printers and charge the client based on this ink usageinformation collected from the multiple printers. The printermanufacturer can expect clients that use many printers will use a largeamount of ink, and providing other value-added services as part of theink billing process can therefore be very effective. If the printermanufacturer deals with numerous companies, it may also be desirable totailor the additional services offered to different clients.

The present invention provides a ink billing system and ink billingmethod that can be beneficially used in systems involving a plurality ofprinters.

SUMMARY OF THE INVENTION

A first aspect of the invention is an ink billing system that is usedbetween a client that prints information and an ink supplier thatsupplies cartridges, which store ink, to the client. On the client side,the ink billing system has a first data processing apparatus; aplurality of second data processing apparatuses each in communicationwith the first data processing apparatus; and a plurality of printerseach comprising a cartridge and each in communication with at least oneof the plurality of second data processing apparatuses for printingbased on commands from the at least one second data processingapparatus, wherein each of the plurality of printers calculates anamount of ink used for printing as an ink usage amount, and sends theink usage amount to at least one of the second data processingapparatuses, and at least one of the second data processing apparatusessends an ink usage amount received from one or more of the plurality ofprinters to the first data processing apparatus. On the ink supplierside, the ink billing system has a terminal device in communication withthe first data processing apparatus for receiving an ink usage amountfrom the first data processing apparatus, wherein the terminal devicestores a billing rate table for calculating a billing rate per ink unit,the billing rate table enables changing the billing rate per ink unitbased on an ink usage amount, and the terminal device calculates aninvoice amount using the billing rate table and the ink usage amountreceived from the first data processing apparatus.

Preferably, the ink billing system further includes a plurality of firstdata processing apparatuses each in communication with the terminaldevice, and wherein the terminal device comprises a separately definedbilling rate table for each of the first data processing apparatuses.

Further preferably, the terminal device generates invoice informationincluding the calculated invoice amount and sends the invoiceinformation to the first data processing apparatus.

Yet further preferably, at least one cartridge stores plural types ofink, and at least one printer calculates an ink usage amount for eachone of the plural types of ink, and sends each calculated ink usageamount through at least one of the second data processing apparatuses tothe first data processing apparatus.

Yet further preferably, the terminal device calculates a number ofcartridges to supply to the client based on the ink usage amountreceived from the first data processing apparatus.

Yet further preferably, at least one of the plurality of printers is aninkjet printer; and the at least one printer calculates an ink usageamount based on the amount of ink discharged from a print head in theprinter.

Preferably, the printer disregards the amount of ink used in operationsfor enabling the print head to discharge ink when calculating the inkusage amount.

Alternatively, at least one of the plurality of printers is a laserprinter; and the at least one printer calculates the ink usage amountbased on a photosensitive drum charging time.

Another aspect of the invention is a ink billing method that is usedbetween a client that uses a plurality of printers to print informationand a ink supplier that supplies ink cartridges to the client, whereinthe steps of the ink billing method are distributed to the printers, afirst data processing apparatus, a plurality of second data processingapparatus and a terminal device. The printer portion of the ink billingmethod comprises calculating an amount of ink used for printing as anink usage amount, and sending the calculated ink usage amount to asecond data processing apparatus. A second data processing apparatusportion of the ink billing method comprises sending the ink usage amountreceived from at least one of the plurality of printers to a first dataprocessing apparatus. A first data processing apparatus portion of theink billing method comprises sending an ink usage amount received fromat least one of a plurality of second data processing apparatuses to aterminal device. A terminal device portion of the ink billing methodcomprises calculating an invoice amount using a billing rate table andthe ink usage amount received from the first data processing apparatus,and changing the billing rate per ink unit in the billing rate tableaccording to the ink usage amount.

Preferably, the terminal device portion of the ink billing methodfurther comprises defining a separate billing rate table for each of aplurality of first data processing apparatuses.

Yet further preferably, the terminal device portion of the ink billingmethod further comprises generating invoice information including thecalculated invoice amount, and sending the invoice information to thefirst data processing apparatus.

Yet further preferably, a cartridge storing plural types of ink isinstalled in at least one of the plurality of printers; and the printerportion of the ink billing method further comprises calculating an inkusage amount for each one of the plural types of ink, and sending eachcalculated ink usage amount through the second data processing apparatusto the first data processing apparatus.

Yet further preferably, the terminal device portion of the ink billingmethod further comprises calculating a number of cartridges to besupplied from the ink supplier to the client based on the ink usageamount received from the first data processing apparatus.

Yet further preferably, at least one of the plurality of printers is aninkjet printer; and the printer portion of the ink billing methodfurther comprises calculating an ink usage amount based on the amount ofink discharged from a print head in the printer.

The inkjet printer preferably disregards the amount of ink used inoperations for enabling the print head to discharge ink when calculatingthe ink usage amount.

Alternatively, at least one of the plurality of printers is a laserprinter; and the printer portion of the ink billing method furthercomprises calculating an ink usage based on the photosensitive drumcharging time.

The present invention enables the ink supplier to provide a plurality ofprinters to a client, calculate how much ink was used by each of theplurality of printers, and invoice the client based on the ink usageinformation collected from the printers. Flexible billing based onprinter usage by the client is also possible by providing the additionalservice of changing the price per unit of ink consumed (referred tobelow as the “unit billing price”) according to how much ink is actuallyused. More particularly, by lowering the unit billing price in steps asink consumption increases, the client can be encouraged to increaseprinter use.

The content of the added services provided can also be changed when theink supplier has multiple client companies by, for example, setting theunit billing price according to the client. The ink billing system andbilling method of the invention thus enables the ink supplier to developa strategic business for increasing customer satisfaction by reducingthe ink cost when the billing system is running and when the system isfirst introduced.

Other objects and attainments together with a fuller understanding ofthe invention will become apparent and appreciated by referring to thefollowing description and claims taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a block diagram of an ink billing system for billing for inkusage using a printer and printing system according to the presentinvention.

FIG. 2 is a schematic block diagram showing the arrangement of anin-store server and printer.

FIG. 3 is a flow chart of the billing status information collectionprocess.

FIG. 4A to FIG. 4D show examples of the ink shot counts in the billingstatus information received from the main server by the printermanufacturer.

FIG. 5 is a graph illustrating the decrease in the unit billing pricebased on ink usage.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

As previously mentioned, to simplify the following discussion, the term“ink” will be used in the specification and the claims as a generic termthat represents, fluids, liquids, or other materials for printing, suchmaterials including ink, toner, organic materials, and the like.

Preferred embodiments of an ink billing system and ink billing methodaccording to the present invention are described below with reference tothe accompanying figures using by way of example a printer and printingsystem according to the present invention.

FIG. 1 is a block diagram of an ink billing system for billing for inkusage using a printer and printing system according to a preferredembodiment of the present invention.

Ink Billing System Concept

In an ink billing system according to this embodiment of the invention,a terminal device 100 run by the printer manufacturer (the supplier ofcartridges containing the ink, and referred to herein as the cartridgesupplier or ink supplier, manages supplying cartridges filled with inkas the ink to company X 200 and company X1 300 (the cartridge user, alsoreferred to herein as the client), which have purchased a plurality ofcolor inkjet printers 240, and company X 200 or company X1 300 pays theprinter manufacturer an ink fee according to the amount of ink that wasused for printing by the printers 240.

In this ink billing system, company X 200 is a company that issuescoupons for particular products and obtains advertising income accordingto the number of coupons issued. For brevity FIG. 1 shows only company X200 and the main server 210 used by company X 200, and company X1 300and the main server 310 used by company X1 300, but there could beadditional client companies. The invention is described using company X200 by way of example.

Company X 200 installs an in-store server (data processing apparatus)220, 230 and a plurality of printers 240 purchased from the printermanufacturer in a plurality of stores 410 to 440 that are owned ormanaged by company Y 400 (such as a customer of company X 200). Only thein-store server and printers in stores 410 and 420 are shown in FIG. 1for brevity. Each printer 240 is in communication via a LAN with thein-store server 220, 230.

Company Y 400 in this example is a supermarket or other retailer. Theprinters 240 can be printers for printing receipts, but are described asseparate from the receipt printers in this embodiment of the invention.More particularly, the printers 240 are installed near the check-outcounter at each POS terminal in each store 410 to 440. Each printer 240is configured to issue coupons, for example, linked to specific productinformation input from the POS terminal according to instructions fromthe in-store server 220, 230 installed in the same store. The issuedcoupons are then handed to the customer by the POS terminal operator ofcompany Y 400.

The main server (data processing apparatus) 210 is maintained by companyX 200, and is in communication via a private or public communicationnetwork such as the Internet with each of the in-store servers 220, 230located in the stores 410 to 440. The main server 210 sends productinformation to the in-store servers 220, 230. The main server 210 isalso used to manage the product information, and sends data used toprint the coupons that are output by the printers 240 in conjunctionwith the product information, and receives from the in-store servers220, 230 information about the type and number of coupons issued by theprinters 240, for example.

The printer manufacturer in this ink billing system supplies inkcartridges (“cartridges” below) containing ink to company X according todemand (ink usage). Demand can be calculated and predicted by theterminal device 100 run by the printer manufacturer based on ink usageby the user. The printers 240 are installed at the checkout counterswith the POS terminals in company Y 400. The ink cartridges supplied bycompany X 200 are installed in the printers 240. A scanner located atthe POS terminal scans the barcode including a product code affixed toeach product, and the in-store server 220, 230 then acquires productinformation corresponding to each product code and determines if thereis coupon information to be printed. If there is coupon information tobe printed, the server sends appropriate print data to the printer 240to issue a coupon. The in-store server 220, 230 (data processingapparatus) in each of the stores 410 to 440 regularly collects(receives) information relating to ink usage from each of the connectedprinters 240 and sends the information to the main server 210.

Regularly or in response to a request from the terminal device 100 ofthe printer manufacturer, the main server 210 of company X 200 thensends the ink usage amount for the printers 240 collected in the mainserver 210 over a network to a terminal device 100 operated by theprinter manufacturer. The ink usage amount collected in the main server210 could alternatively be recorded on a CD (Compact Disc), DVD (DigitalVersatile Disc), or other data storage medium which is then delivered tothe printer manufacturer. The printer manufacturer or terminal device100 then tabulates the ink usage amount received from company X 200 andperiodically bills company X 200 for the ink usage. The terminal device100 produces billing information including the calculated ink fee andsends the billing information over the network to the main server 210.Based on this billing information, company X 200 then remits payment tothe printer manufacturer via the main server 210 executing an on-linepayment transaction with a bank, for example.

The company X 200 also returns empty ink cartridges collected fromcompany Y 400 to the printer manufacturer. The printer manufacturerrefills the returned ink cartridges and then returns the refilled inkcartridges to company X 200.

The ink billing system according to this embodiment of the inventiononly bills for the amount of ink used for printing coupons and othercontent. Ink that is not used for printing includes, for example, inkthat is consumed by cleaning processes, print head recovery processes,and ink path charging operations, including the ink that is used toflush the nozzles and ink that is vacuumed from the nozzles as part ofprint head nozzle maintenance. More specifically, there is no charge forink that is consumed by operations that are run so that ink can bedischarged from the print head in order to print. An advantage of thissystem is therefore that company X 200 does not need to pay for ink thatis not used to print the coupons.

Relationship Between the In-Store Server and Printers

The relationship between the in-store server 220 (230) and printers 240of the printing system according to this embodiment of the invention isdescribed next with reference to FIG. 2.

FIG. 2 is a schematic block diagram showing the arrangement of thein-store server 220 (230) and printer 240.

As shown in FIG. 2 the main parts of the in-store server 220 (orin-store server 230 or other servers) are the CPU 221, ROM 222(nonvolatile memory), RAM 223 (volatile memory), a hard disk drive 224as a large capacity storage device, an input device 225, andcommunication interface 226. The in-store server 220 controls theprinter 240 as a result of the CPU 221 running the operating system andsoftware applications stored in the hard disk drive 224, and sendingcommands and print data to the printer 240 through communicationinterface 226.

The printer 240 is composed primarily of a CPU 241, flash ROM 242(rewritable nonvolatile memory), RAM 243 (volatile memory),communication interface 244, a printing control unit 245 for controllingdischarging ink onto roll paper to print, a paper transportationmechanism 246, a print head 247, and an cartridge compartment 15 intowhich the ink cartridge 20 is loaded. The printer 240 receives commandsand print data by communicating with the in-store server 220 through thecommunication interface 244 while the CPU 241 runs firmware stored inflash ROM 242. Based on the received print data, the printing controlunit 245 conveys roll paper using the paper transportation mechanism 246while driving the print head 247 to print on the roll paper to issuecoupons.

The CPU 241 controls a shot count analyzing unit 309 by running aspecific program stored in flash ROM 242. Alternatively, the CPU 241controls a charging time counting unit 309A by running a specificprogram stored in flash ROM 242.

The shot count analyzing unit 309 counts the ink droplets dischargedfrom the print head 247 as the number of shots of each color of ink indot units based on the print data or the dot pattern data generated fromthe print data. The ink cartridge typically will store plural types(colors) of ink, e.g. cyan, magenta, yellow, and black. The shot countanalyzing unit 309 counts the number of shots for each of the pluraltypes (colors) of ink. The amount of ink discharged from the print head247 differs according to the size of each dot, that is, whether each dotis small, medium, or large. The shot count analyzing unit 309 convertseach size of dot to a corresponding shot count, and calculates how manyshots were discharged. The shot counts calculated by the shot countanalyzing unit 309 are then stored in flash ROM 242. The cumulative shotcount from a particular point in time, such as when the ink cartridge 20is replaced, is also stored. The shot count analyzing unit 309 can alsocalculate ink usage from the shot count.

The shot count analyzing unit 309 counts the ink droplets dischargedfrom the print head 247 to print on the roll paper in dot unitsconverted to a shot count for each color, and does not count as part ofink usage amount the ink discharged from the print head 247 duringnozzle flushing or the ink vacuumed from the print head 247 by an inksuction mechanism (not shown) for example.

Acquiring Billing Status Information from the Printer

The shot count calculated by the shot count analyzing unit 309 is sentregularly or in response to a request from the in-store server 220 fromthe printer 240 to the in-store server 220 as part of the billing statusinformation used for billing. In addition to the shot count, the billingstatus information includes the printer serial number, remaining inklevel, and ink cartridge IDs. At a predetermined time or in response toa request from the in-store server 220, the billing status informationis then collected on (sent to) the main server 210. The billing statusinformation stored on the main server 210 is sent regularly, or inresponse to a request from the in-store server 220, to the terminaldevice 100. The terminal device 100 of the printer manufacturer can thendetermine ink usage by the printers 240 and the condition of each inkcartridge 20.

This process is described in further detail below with reference to FIG.3.

FIG. 3 is a flow chart illustrating the billing status informationcollection process.

First, each printer 240 counts and calculates the total number of shotsusing the shot count analyzing unit 309 and thus collects the billingstatus information (step S21).

The in-store server 220 collects the billing status information fromeach of the printers 240 at a predetermined time or when requested bysending a billing status information transmission request to all of theprinters 240 in the store (step S31).

When a printer 240 receives a billing status information transmissionrequest (step S22), the printer 240 generates the billing statusinformation including the shot count (step S23) and sends the resultingbilling status information to the in-store server 220 (step S24). Thein-store server 220 then receives and stores the billing statusinformation from the printer 240 (step S32).

The printer 240 then returns to step S21 to continue collecting thebilling status information and repeats steps S22 to S26. As a result,the printer 240 can send the billing status information to the in-storeserver 220 whenever a billing status information transmission request isreceived.

After receiving the billing status information from the printers 240 byway of the in-store server 220 (230), the main server 210 sends abilling status information transmission request at a predetermined timeor as required to all of the in-store servers 220 (230) (step S41).

When a billing status information transmission request is received (stepS33), the in-store server 220, 230 sends the stored billing statusinformation to the main server 210 (step S34). When the main server 210receives billing status information from an in-store server 220, 230(step S42), the main server 210 stores the billing status information.As a result, billing status information is collected by the main server210 from all printers 240 insofar as the printers 240 are operatingnormally, that is, unless there is a problem with a particular printer240 or a printer 240 is turned off.

When requested by the terminal device 100 of the printer manufacturer ata predetermined time or as needed, the main server 210 sends the billingstatus information collected from all printers to the terminal device100 used by the printer manufacturer (step S43). The billing statusinformation can be sent on-line or the billing status information couldbe recorded on a recordable data storage medium such as a CD or DVD thatis delivered to the printer manufacturer. As a result, all billingstatus information stored on the main server 210 is transmitted ordelivered to the printer manufacturer or the terminal device 100designated by the printer manufacturer.

Requests from the terminal device 100 of the printer manufacturer do notneed to be processed on demand. Alternatively, the company X 200 couldassemble the billing status information according to a predeterminedmonthly schedule and send the monthly billing status information to theterminal device 100 designated by the printer manufacturer by a certaindate each month, for example.

Tabulation by the Printer Manufacturer

The terminal device 100 of the printer manufacturer determines the totalink shot count (ink usage amount) by tabulating the ink shot countinformation in the billing status information.

The ink shot count indicates how much ink was used by each printer 240each month, for example, and billing is based on this ink shot count.

FIG. 4A to FIG. 4D show the ink shot counts from the billing statusinformation received by the printer manufacturer's terminal device 100from the main server 210 of company X 200. For brevity, the invention isused in an ink billing system having a maximum of three printers 240 inthis example. FIG. 4A shows the ink shot count tabulation data for theperiod from the introduction of the ink billing system to Jul. 1, 2006,and FIG. 4B to FIG. 4D show the ink shot count tabulation data for therespective one month periods starting Aug. 1, 2006. For brevity, thetotal ink shot counts are not shown for each color in FIG. 4A to FIG.4D, and the total ink shot count for all colors combined is shown by wayof example.

As shown in FIG. 4A, two printers were in use as of Jul. 1, 2006. The“previous count” in each table in FIG. 4A to FIG. 4D is the total inkshot count as of the last tabulation, and is 0 in FIG. 4A because thebilling system was just introduced. The “received count” is based on thebilling status information received by the terminal device 100designated by the printer manufacturer from the main server 210 (companyX) for the current billing (tabulation) cycle, and the “difference” isthe difference of the received count minus the previous count. The“current count” is a value corresponding to the ink shot count used byeach printer 240 as known to the terminal device 100 of the printermanufacturer based on the received count at the current tabulation date,and is normally equal to the current received count. This “currentcount” becomes the previous count that is the basis for the nexttabulation.

Each printer 240 stores the cumulative ink shot count calculated fromthe start of operation, and reports this cumulative ink shot count tothe terminal device 100 designated by the printer manufacturer at eachtabulation date. As a result, the ink usage amount from the previoustabulation date to the current tabulation date is denoted by the“difference” value in each table.

The total of these differential counts obtained for each printer 240therefore denotes the total ink usage amount by company X 200 from theprevious tabulation to the current tabulation. The terminal device 100of the printer manufacturer can therefore calculate and determine thebilling amount from the previous tabulation to the current tabulation,that is, the current billing period, by multiplying the ink cost pershot times this total ink usage amount. The terminal device 100 of theprinter manufacturer then generates and sends billing information basedon this billing amount to the main server 210 of company X 200, and thecompany X 200 remits payment for the invoiced amount to the printermanufacturer.

To complete the transaction, the company X 200 runs a paymentapplication stored on the main server 210, for example, to transferfunds to the bank account designated by the printer manufacturer basedon the received billing information by way of a bank server (not shown)that is connected to the main server 210 over a network. Alternatively,the printer manufacturer could send a conventional invoice to thecompany X 200 based on the invoice amount calculated by the terminaldevice 100, and the company X 200 could remit payment to the printermanufacturer based on the invoice by the desired form of payment, e.g.check.

The data table in FIG. 4B shows that the number of printers hasincreased from the number of printers reporting in FIG. 4A. This isbecause a new printer was added to the printing system by company X andan ink shot count carrying a printer serial number corresponding to thenew printer is transmitted with the billing status information. A newprinter record based on this information is therefore added to the datatable, and the customer is billed based on the total number of ink shotsreported by all printers, including the new printer.

If billing status information is not reported by a particular printer240 for some reason, such as the printer 240 being turned off when thedata is reported, the record for that printer is blank as shown in FIG.4C. The difference field is therefore also blank (equals 0), notincluded in the total count, and the current count of that printer 240for the current billing period is the previous count.

When billing status information is received for the same printer 240 thenext time the billing status information is reported as shown in FIG.4D, the received count is the total ink shot count for two billingperiods, and the ink usage that was not previously reported or billedfor is added to the current billing amount.

This data collection and tabulation process assures that the printermanufacturer can reliably bill the customer for ink usage by eachprinter 240 even when the printers 240 are located remotely from theterminal device 100 of the printer manufacturer. If billing statusinformation is not received from a particular printer 240 for a certainperiod of time, a problem may have occurred and an inquiry can also beinitiated.

Billing According to Ink Consumption

The terminal device 100 of the printer manufacturer in this embodimentof the invention provides company X 200 with the added service ofadjusting the price per unit of ink (billing rate) consumed according tohow much ink is used in a specific billing period, such as a month orother unit of time.

More specifically, the terminal device 100 of the printer manufacturerstores a billing rate table such as graphically represented in FIG. 5and defines a billing method that gradually reduces the unit cost of ink(billing rate) in steps as the ink shot count rises. This enables theprinter manufacturer or the terminal device 100 designated by theprinter manufacturer that supplies the ink cartridges to discount thecost of ink for a particular client company X 200 based on how much inkthe client uses. This helps promote even greater use of inkjet printersby the company X 200 and enables the supplier to develop a strategicbusiness plan for improving customer satisfaction by reducing the costof ink starting from the time the ink billing system is introduced.

In addition, if a different client company X1 300 uses even more inkthan company X 200, a different billing table using a lower rate thanoffered to company X 200 can be used, or a billing table that reducesthe cost of ink continuously linearly as ink usage increases can be usedto even further discount the cost of ink. The printer manufacturer cantherefore vary the content of the added service provided to eachcustomer when the printer manufacturer deals with multiple companies,and can therefore adapt the business strategy to market conditions.

The billing rate tables maintained by the terminal device 100 of theprinter manufacturer can be changed independently, and can be changed orupdated as needed using an input device not shown. Alternatively, therate table can be changed according to defined rules, such as loweringthe billing rate for a particular client to a specific level when thetotal ink usage in a specified period of time reaches a specified level.This is accomplished by running an appropriate billing applicationstored on the terminal device 100 of the printer manufacturer.

Furthermore, by knowing the ink usage as described above, the terminaldevice 100 of the printer manufacturer can also provide an ink cartridgeinventory management service for the client company X 200. Morespecifically, the printer manufacturer can predict when ink cartridgeswill be depleted based on the ink shot count information, and based onthis information can resupply the company X 200 with the required numberof ink cartridges in a timely manner so that the company X 200 does notrun out of ink cartridges.

Being able to predict ink cartridge depletion also makes productionscheduling and management easier for the printer manufacturer, andeliminates concerns about carrying excessive inventory.

The invention is described herein as billing for ink usage based on inkshot count information, but the invention is not so limited and the billfor ink usage can be based on a different unit of measure such as howmany coupons are printed, that is, how much printed matter is printed.In this scenario the terminal device 100 of the printer manufactureracquires the printed coupon count instead of the ink shot count from themain server 210 of the company X 200, sets a fee for each coupon, andbills the client accordingly. The ink usage fee can also be discountedaccording to the number of coupons printed in one month or otherspecified unit of time.

The printer manufacturer is the ink cartridge supplier in thisembodiment of the invention, but the invention is not so limited. Amiddleman such as an ink cartridge supply company or an ink cartridgemanufacturer that manufactures and sells just ink cartridges couldfunction between the printer manufacturer and the client company X 200.

The invention is described using an inkjet printer by way of example,but the invention is not so limited and can be used with laser printers,for example. In this case toner is used instead of ink, and thephotosensitive drum charging time is measured instead of the ink shotcount. A charging time counting unit 309A is used instead of the shotcount analyzing unit 309 described above to count the drum chargingtime, and the drum charging time is sent to the server as the billingstatus information instead of the ink shot count.

Toner for forming images is stored in the toner cartridges used in laserprinters, and toner use depends on this photosensitive drum chargingtime. The client server can therefore calculate toner usage based on thecharging time determined by the charging time counting unit, and aterminal device run by the toner cartridge supplier can invoice theclient based on the reported charging time. Toner usage could also becalculated and sent by the laser printer to the client server.

In addition to this charging time information, printer serial numbers,remaining toner level, toner cartridge ID, and other information canalso be sent as part of the billing status information and used fortoner cartridge management.

Although the present invention has been described in connection with thepreferred embodiments thereof with reference to the accompanyingdrawings, it is to be noted that various changes and modifications willbe apparent to those skilled in the art. Such changes and modificationsare to be understood as included within the scope of the presentinvention as defined by the appended claims, unless they departtherefrom.

What is claimed is:
 1. An ink billing system that is used between aclient that prints information and an ink supplier that suppliescartridges, which store ink, to the client, the ink billing systemcomprising: on the client side a first data processing apparatus; aplurality of second data processing apparatuses each in communicationwith the first data processing apparatus; and a plurality of printerseach comprising a cartridge storing ink and a print head having nozzlesfor discharging the ink, each of the printers being in communicationwith, and receiving print data from at least one of the plurality ofsecond data processing apparatuses, and wherein each of the plurality ofprinters discharges first ink from the nozzles onto paper based on thereceived print data for printing, discharges second ink from the nozzlesfor cleaning or recovering the nozzles, the second ink being consumed inthe cleaning or recovering without being discharged onto the paper, andcalculates an ink usage amount based on only the first ink by countingshots discharged from the nozzles, and wherein at least one of thesecond data processing apparatuses sends the ink usage amount receivedfrom one or more of the plurality of printers to the first dataprocessing apparatus; and on the ink supplier side a terminal device incommunication with the first data processing apparatus for receiving theink usage amount from the first data processing apparatus, wherein theterminal device stores a billing rate table defining a unit cost of ink,the billing rate table enables changing the unit cost of ink based on anink usage amount consumed in a predetermined period, and the terminaldevice calculates an invoice amount using the billing rate table and theink usage amount received from the first data processing apparatus. 2.The ink billing system described in claim 1, further comprising: aplurality of first data processing apparatuses each in communicationwith the terminal device, and wherein the terminal device comprises aseparately defined billing rate table for each of the first dataprocessing apparatuses.
 3. The ink billing system described in claim 1,wherein: the terminal device generates invoice information including thecalculated invoice amount and sends the invoice information to the firstdata processing apparatus.
 4. The ink billing system described in claim1, wherein: at least one cartridge stores plural types of ink; and atleast one printer calculates an ink usage amount for each one of theplural types of ink, and sends each calculated ink usage amount throughat least one of the second data processing apparatuses to the first dataprocessing apparatus.
 5. The ink billing system described in claim 1,wherein: the terminal device calculates a number of cartridges to supplyto the client based on the ink usage amount received from the first dataprocessing apparatus.
 6. An ink billing method that is used between aclient, which uses a plurality of printers to print information, and anink supplier that supplies cartridges that store ink to the client,wherein: a printer portion of the ink billing method comprises: using aprinter having a cartridge storing ink to print a plurality of dotsusing a print head having nozzles for discharging the ink, the printerbeing in communication with, and receiving data from, a second dataprocessing apparatus, and receive print data, discharge first ink fromthe nozzles onto paper based on the received print data for printing,discharge second ink from the nozzles for cleaning or recovering thenozzles, the second ink being consumed in the cleaning or recoveringwithout being discharged onto the paper, calculate an ink usage amountbased on only the first ink by counting shots discharged from thenozzles, and send the calculated ink usage amount to the second dataprocessing apparatus; a second data processing apparatus portion of theink billing method comprises: sending the ink usage amount received fromat least one of the plurality of printers to a first data processingapparatus; a first data processing apparatus portion of the ink billingmethod comprises: sending the ink usage amount received from the seconddata processing apparatuses to a terminal device; and a terminal deviceportion of the ink billing method comprises: using a terminal device tostore a billing rate table defining a unit cost of ink; and change theunit cost of ink in the billing rate table according to an ink usageamount consumed in a predetermined period; and calculate an invoiceamount using the billing rate table and the ink usage amount receivedfrom the first data processing apparatus.
 7. The ink billing methoddescribed in claim 6, wherein the terminal device portion of the inkbilling method further comprises: defining a separate billing rate tablefor each of a plurality of first data processing apparatuses.
 8. The inkbilling method described in claim 6, wherein the terminal device portionof the ink billing method further comprises: generating invoiceinformation including the calculated invoice amount; and sending theinvoice information to the first data processing apparatus.
 9. The inkbilling method described in claim 6, wherein: a cartridge storing pluraltypes of ink is installed in at least one of the plurality of printers;and the printer portion of the ink billing method further comprises:calculating an ink usage amount for each one of the plural types of ink,and sending each calculated ink usage amount through the second dataprocessing apparatus to the first data processing apparatus.
 10. The inkbilling method described in claim 6, wherein the terminal device portionof the ink billing method further comprises: calculating a number ofcartridges to be supplied from the ink supplier to the client based onthe ink usage amount received from the first data processing apparatus.